The electromagnetically transparent material refers to a material that allows an electromagnetic wave to transmit therethrough and hardly changes the properties (including energy) of the electromagnetic wave. The electromagnetically transparent material is widely applied to the fields of aviation, aerospace, military equipment, radio equipment and so on, and functions to satisfy the performance requirements such as reception, transmission, amplification, mixing and radiation of microwave/millimeter-wave signals or to prevent the incident electromagnetic wave from being massively reflected so as to evade the rival's radar detection. The conventional electromagnetically transparent material is a fiber-reinforced resin-based composite material whose transparent property is related with the kind of fibers, the resin matrix, and interfacial properties of the composite material; and the influences of the fibers and the resin matrix on the transparent property of the material depend on the dielectric properties of the fibers and the resin matrix. Because the transparent property of such a conventional electromagnetically transparent material depends on the transparent property of the material itself, both the physical property and the transparent property of the conventional electromagnetically transparent material are not suitable for severe external environments (e.g., at a high temperature or under a high pressure). As a result, the conventional electromagnetically transparent material has a narrow application scope. Moreover, it is complex to adjust electromagnetic parameters of the conventional electromagnetically transparent material because compositions and components of the conventional electromagnetically transparent material must be adjusted with respect to different wavebands of the electromagnetic wave respectively. Consequently, a great amount of experimental verifications is required and the manufacturing cost is high.